Signs are very important - but carefully consider your placement of them. All too often, events put lots of nice signage out that looks fine during setup when the place is empty. But when the area is crowded, signs are hidden. The worst is when the only signage is at waist level in front of tables. They are invisible as soon as a few people get in line. You probably want those - but also have ones HIGH that people can see above the crowd. If you have lines or paths, make it clear where someone should go. It's so frustrating not to even know if one is in the RIGHT long line.
Have plenty of event helpers, make them very visible with a specific t-shirt or vest, and have them armed with the knowledge they need to answer questions. An centrally placed, clearly marked information desk is good.
Think about any measures you can take to shorten lines or wait times. For example, if they are in lines buying tickets or registering, make sure they know exactly what to do before their turn arrives. At our elementary Spring Fling we handed out a program before they even entered the building that included all activities, costs, number of tickets needed for each, and key details. We had staff working the ticket line pointing out these details in the program so the attendees could already cacluate how many tickets they wanted before they got to the front. Otherwise, every buyer needed a consultation once they get to the cashier.
Give people information. I run a work event where 300 people get in line all at once to eat. At first glance, the line seems really long, stretching halfway around the exhit hall. But we make repeated announcements that when they get towards the front, it breaks into SIX buffet lines, moves quickly, and there's plenty of food. People relax and spend their few minutes in line chatting because they've been reassured.
Very carefully consider traffic flow for where your people pass through areas - especially with the silent auction. And print all your bid sheets with big clear letters that are easy to read at a glance. Don't create any dead end spaces - make sure the peole can keep walking without turning around.
If there are lines, plan for them with roped lanes, placement out of the general flow of traffic, and entertainment if possible. At our Breakfast with Santa, the line for pictures would get pretty long. But we placed it where those waiting had a good view of the stage where Christmas karoke songs were going on. So the people in line could watch or join in with the songs while they waited.
Watch how stores and fast food restaurants handle lines. You can pick up some good tips there - like an express line for exact change or simple transactions.
Good luck!
